Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE

Inverse crossover resonance in the Doppler-free 87 Rb spectrum

Igor M. Beterov, I. I. Ryabtsev, Vasily M. Entin, V. B. Elman

Published Feb 5, 1999• 0 citations
Publisher

Abstract

We report about an experimental observation of alignment induced resonance in Doppler free spectrum of D2 absorption line of 87Rb ((lambda) equals 780 nm). The resonance appeared as a peak of absorption instead of transmission at the position of crossover resonance between the 5S1/2(F equals 1) yields 5P3/2(F' equals 0) and the 5S1/2(F equals 1) yields 5P3/2(F' equals 1) transitions.

DOI
10.1117/12.340001

Related papers

Laser frequency stabilization using bichromatic crossover spectroscopy

Taek Jeong, Han Seb Moon

We propose a Doppler-free spectroscopic method named bichromatic crossover spectroscopy (BCS), which we then use for the frequency stabilization of an off-resonant frequency that does not correspond to an atomic transition. The observed BCS in the 5S1/2 → 5P1/2 transition of 87Rb is related to the hyperfine structure of the conventional saturated absorption spectrum of this transition. Furthermore, the Doppler-free BCS is numerically calculated by considering all of the degenerate magnetic sublevels of the 5S1/2 → 5P1/2 transition in an atomic vapor cell, and is found to be in good agreement with the experimental results. Finally, we successfully achieve modulation-free off-resonant locking at the center frequency between the two 5S1/2(F = 1 and 2) → 5P1/2(F′ = 1) transitions using a polarization rotation of the BCS. The laser frequency stability was estimated to be the Allan variance of 2.1 × 10−10 at 1 s.

Journal of Applied Physics•Mar 3, 2015•5 citations

Observation of an electromagnetically induced change of absorption in multilevel rubidium atoms

Yongqing Li, Shaozheng Jin, Min Xiao

A 64.4% reduction in absorption at the rubidium D2 line is observed when a pumping field at 775.8 nm is tuned on resonance to the transition between the excited states 5${\mathit{P}}_{3/2}$ and 5${\mathit{D}}_{5/2}$. As the pumping field is tuned off resonance, an absorption peak appears at the side of the Doppler-broadened D2 line. This modification in absorption is related to pumping-induced atomic coherence in this three-level ladder-type system. This experiment is done in a Rb vapor cell at room temperature and with cw diode lasers for both pumping and probe beams in a Doppler-free configuration.

Physical Review A•Mar 1, 1995•64 citations

Double-Frequency Doppler-Free Spectroscopy of 87Rb Atoms

Vladimir L Velichansky, Kirill M. Sabakar, A. S. Fedorov +5 more

We investigate Doppler-free absorption lines induced by counter-propagating polychromatic optical fields in the D1 line of 87Rb atoms. Cases of orthogonal and parallel polarizations are considered. The resonance associated with Fe = 1 demonstrates unusual behaviour with two-photon detuning: the amplitude grows while the width becomes smaller. The crossover resonance involving transitions to both sublevels Fe = 1, 2 of the excited state is more pronounced at parallel polarizations than at orthogonal and has smaller width compared to the lines corresponding to atomic transitions. A qualitative explanation of experimentally observed features is given.

Journal of Experimental and Theoretical Physics Letters•Apr 1, 2025•3 citations

Comparison between transparencies of 5S_1/2-5P_3/2-4D_5/2 and 5S_1/2-5P_3/2-5D_5/2 transitions of ^87Rb atoms

Han Seb Moon, Heung‐Ryoul Noh

We have experimentally and theoretically studied the causes of the transparency spectra of the 5S1/2-5P3/2-4D5/2 and 5S1/2-5P3/2-5D5/2 transitions of 87Rb atoms. Although, the two-photon resonance of the 5S1/2-5P3/2-4D5/2 transition was not Doppler-free in an Rb vapor, we observed the transparency phenomenon in this transition. The main cause of the transparency of the 5S1/2-5P3/2-4D5/2 transition was double-resonance optical pumping (DROP) due to two-step excitation, and that of the 5S1/2-5P3/2-5D5/2 transition was DROP and electromagnetically induced transparency due to two-photon coherence. We confirmed the experimental results with theoretical results calculated using the density matrix equations considering all the degenerate magnetic sublevels of both transitions of the 87Rb atoms.

Journal of the Optical Society of America B•Jun 7, 2012•15 citations

Influence of Intensity Ratio of Resonant Spectral Components on Q-Factor of Dual-Frequency Doppler-Free Resonance in 87Rb Atoms

Kirill M. Sabakar, Eugene A. Tsygankov, Dmitry S. Chuchelov +4 more

Abstract Doppler-free resonance of the 87Rb D1 line induced by bichromatic counter-propagating waves with different intensity ratios of the two resonant spectral components is investigated. It is shown that the maximal amplitude is achieved at unequal intensities for the low-frequency eigen and crossover resonances, and at equal intensities for the high-frequency eigen resonance. Measurements of the Q-factor (the contrast-to-width ratio) demonstrate that for all studied resonances, its maximal value is attained at an intensity ratio different from 1. For the low-frequency eigen resonance, the maximal Q-factor enhances by a factor of six at an intensity ratio of 5 as compared to the case of equal intensities.

Bulletin of the Russian Academy of Sciences Physics•May 1, 2026•0 citations

Saturated absorption spectroscopy: Elimination of crossover resonances with the use of a nanocell

Armen D. Sargsyan, David G. Sarkisyan, A. Papoyan +6 more

It is demonstrated that the velocity-selective optical pumping/saturation resonances of the reduced absorption in a Rb vapor nanocell with thickness L = λ, 2λ, and 3λ (resonant wavelength λ = 780 nm) allow for the complete elimination of crossover (CO) resonances. We observe well-pronounced resonances corresponding to the F g = 3 → F e = 2, 3, and 4 hyperfine transitions of the 85Rb D2 line with line widths close to the natural width. A small CO resonance located midway between F g = 3 → F e = 3 and F g = 3 → F e = 4 transitions appears only for L ≥ 4λ. The D2 line (λ = 852 nm) in a Cs nanocell exhibits a similar behavior. From the amplitude ratio of the CO and VSOP resonances, it is possible to determine the thickness of the column of alkali vapor in the range of 1–1000 μm. The absence of the CO resonances for nanocells with L ∼ λ is attractive for the frequency reference application and for studying the transitions between the Zeeman sublevels in external magnetic fields.

arXiv:0711.1684•Laser Physics•Jun 1, 2008•30 citations
We report about an experimental observation of alignment induced resonance in Doppler free spectrum of D2 absorption line of 87Rb ((lambda) equals 780 nm). The resonance appeared as a peak of absorption instead of transmission at the position of crossover resonance between the 5S1/2(F equals 1) yields 5P3/2(F' equals 0) and the 5S1/2(F equals 1) yields 5P3/2(F' equals 1) transitions.
We propose a Doppler-free spectroscopic method named bichromatic crossover spectroscopy (BCS), which we then use for the frequency stabilization of an off-resonant frequency that does not correspond to an atomic transition. The observed BCS in the 5S1/2 → 5P1/2 transition of 87Rb is related to the hyperfine structure of the conventional saturated absorption spectrum of this transition. Furthermore, the Doppler-free BCS is numerically calculated by considering all of the degenerate magnetic sublevels of the 5S1/2 → 5P1/2 transition in an atomic vapor cell, and is found to be in good agreement with the experimental results. Finally, we successfully achieve modulation-free off-resonant locking at the center frequency between the two 5S1/2(F = 1 and 2) → 5P1/2(F′ = 1) transitions using a polarization rotation of the BCS. The laser frequency stability was estimated to be the Allan variance of 2.1 × 10−10 at 1 s.
A 64.4% reduction in absorption at the rubidium D2 line is observed when a pumping field at 775.8 nm is tuned on resonance to the transition between the excited states 5P3/2{\mathit{P}}_{3/2}P3/2​ and 5D5/2{\mathit{D}}_{5/2}D5/2​. As the pumping field is tuned off resonance, an absorption peak appears at the side of the Doppler-broadened D2 line. This modification in absorption is related to pumping-induced atomic coherence in this three-level ladder-type system. This experiment is done in a Rb vapor cell at room temperature and with cw diode lasers for both pumping and probe beams in a Doppler-free configuration.
We investigate Doppler-free absorption lines induced by counter-propagating polychromatic optical fields in the D1 line of 87Rb atoms. Cases of orthogonal and parallel polarizations are considered. The resonance associated with Fe = 1 demonstrates unusual behaviour with two-photon detuning: the amplitude grows while the width becomes smaller. The crossover resonance involving transitions to both sublevels Fe = 1, 2 of the excited state is more pronounced at parallel polarizations than at orthogonal and has smaller width compared to the lines corresponding to atomic transitions. A qualitative explanation of experimentally observed features is given.
We have experimentally and theoretically studied the causes of the transparency spectra of the 5S1/2-5P3/2-4D5/2 and 5S1/2-5P3/2-5D5/2 transitions of 87Rb atoms. Although, the two-photon resonance of the 5S1/2-5P3/2-4D5/2 transition was not Doppler-free in an Rb vapor, we observed the transparency phenomenon in this transition. The main cause of the transparency of the 5S1/2-5P3/2-4D5/2 transition was double-resonance optical pumping (DROP) due to two-step excitation, and that of the 5S1/2-5P3/2-5D5/2 transition was DROP and electromagnetically induced transparency due to two-photon coherence. We confirmed the experimental results with theoretical results calculated using the density matrix equations considering all the degenerate magnetic sublevels of both transitions of the 87Rb atoms.
Abstract Doppler-free resonance of the 87Rb D1 line induced by bichromatic counter-propagating waves with different intensity ratios of the two resonant spectral components is investigated. It is shown that the maximal amplitude is achieved at unequal intensities for the low-frequency eigen and crossover resonances, and at equal intensities for the high-frequency eigen resonance. Measurements of the Q-factor (the contrast-to-width ratio) demonstrate that for all studied resonances, its maximal value is attained at an intensity ratio different from 1. For the low-frequency eigen resonance, the maximal Q-factor enhances by a factor of six at an intensity ratio of 5 as compared to the case of equal intensities.
It is demonstrated that the velocity-selective optical pumping/saturation resonances of the reduced absorption in a Rb vapor nanocell with thickness L = λ, 2λ, and 3λ (resonant wavelength λ = 780 nm) allow for the complete elimination of crossover (CO) resonances. We observe well-pronounced resonances corresponding to the F g = 3 → F e = 2, 3, and 4 hyperfine transitions of the 85Rb D2 line with line widths close to the natural width. A small CO resonance located midway between F g = 3 → F e = 3 and F g = 3 → F e = 4 transitions appears only for L ≥ 4λ. The D2 line (λ = 852 nm) in a Cs nanocell exhibits a similar behavior. From the amplitude ratio of the CO and VSOP resonances, it is possible to determine the thickness of the column of alkali vapor in the range of 1–1000 μm. The absence of the CO resonances for nanocells with L ∼ λ is attractive for the frequency reference application and for studying the transitions between the Zeeman sublevels in external magnetic fields.